Microsoft Office Professional Plus 2021-2024 V2412 Build May 2026

Despite rigorous testing, users have reported edge cases with the December 2024 build:

Issue: Outlook crash when opening a shared calendar from Exchange 2016. Fix: The V2412 build includes a hotfix for outlook.exe heap corruption. Install the update cleanly via ODT.

Issue: Excel "Not Responding" when using Power Query with MySQL connectors. Workaround: Downgrade the MySQL ODBC driver to version 8.0.32. A permanent fix is promised for Build 2413 (January 2025).

Issue: The "Save As" dialog defaults to OneDrive instead of This PC. Fix: Registry modification: HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office\16.0\Common\General\PreferCloudSaveLocations set to 0. Microsoft Office Professional Plus 2021-2024 V2412 Build

Here is where the review gets interesting. The v2412 build highlights a growing divide.

Microsoft is aggressively pushing AI (Copilot) into Microsoft 365. If you are a creative writer or a data analyst who needs AI to generate drafts or summarize meetings, Office Professional Plus will feel incomplete. It does not have the cloud-connected AI features of its subscription brother.

However, for many—lawyers drafting contracts, accountants balancing books, students writing theses—this is a feature, not a bug. The v2412 build offers a "quiet" Office. It respects your privacy by keeping the processing local. It respects your workflow by not interrupting you with "smart suggestions" you didn't ask for. Despite rigorous testing, users have reported edge cases

Unlike Microsoft 365, which updates automatically, Office 2021 perpetual licenses require active deployment via the Office Deployment Tool (ODT).

Microsoft has finally pushed the Fluent Design System fully into the LTSC branch. The sharp, utilitarian edges of Office 2016 and 2019 are gone, replaced by soft, rounded corners and a depth effect that makes the ribbon look like it’s floating slightly off the page.

It sounds minor, but when you stare at a spreadsheet for 8 hours, the softer UI is genuinely easier on the eyes. The dark mode is also significantly improved in v2412, no longer looking like a high-contrast hack, but a legitimate, sleek interface. Furthermore, the V2412 build enforces TLS 1

If you are an IT manager running Office Professional Plus 2021, updating to the V2412 Build is not optional—it is a security imperative. The original release of Office 2021 (Version 2108) is now three years old. Attackers have had three years to reverse-engineer its defenses.

The December 2024 update (Build 2412) patches 12 CVEs, including:

Furthermore, the V2412 build enforces TLS 1.3 by default for all cloud connections, deprecating the insecure TLS 1.0 fallbacks present in the original 2021 gold build.